1. Technical Field
The present invention relates to a display method and a display device for displaying the speed and the number of rotations of an engine of a moving body, such as a vehicle, an airplane, a ship, or an electric train.
2. Related Art
In recent years, organic electroluminescent (hereinafter, referred to as EL) panels using organic EL elements have attracted considerable attention since they have lower power consumption, wider viewing angle, and higher contrast than other devices. There is known an organic EL display device using the organic EL panel (for example, see JP-A-2004-127924).
As a conventional vehicle information display device mounted in an instrument panel of a vehicle, such as an automobile, there is known a liquid crystal display device (a multi-display device) for displaying a plurality of images on a screen (for example, see JP-A-2004-291731). Such a vehicle information display device performs three types of display operations by using a first display unit, serving as a speedometer for indicating the speed of the vehicle, a second display unit, serving as a tachometer for indicating the number of rotations of an engine, and a third display unit for displaying, for example, map information of a car navigation apparatus in a liquid crystal panel.
However, it is considered that the convent-ional organic EL display device disclosed in JP-A-2004-127924 is mounted in an instrument panel of a vehicle, such as an automobile, and a plurality of different images are switchably displayed on the same display panel of the same display device such that portions of the images overlap each other.
For example, it is considered that, as the plurality of different images, the image of a speedometer for indicating the speed of a moving body and the image of a tachometer for indicating the number of rotations of an engine are switchably displayed such that portions of the images overlap each other. In this case, when an image R (for example, the image of the speedometer) having a white image portion is displayed on a portion of a display panel at one time and then an image S (for example, the image of the tachometer) having a white image portion overlapping the white image portion of the image R is displayed thereon, burning occurs in an overlapping portion between the image R and the image S, which makes it difficult to obtain high-quality display.